An electronic laryngoscope is usually composed of a camera, a hollow hard tube (or “connecting rod”), a handle and a control display module. A camera is provided on the front end of the hollow hard tube and the rear end thereof is fixedly connected to the handle, and wires can be routed inside the hollow hard tube. The rear portion of the handle is connected to the control display module. In the process of diagnosis using the electronic laryngoscope, it is usually used with a tracheal hose (or “tracheal cannula”, “tracheal catheter”, “insert tube”), that is, inserting the hollow hard tube of the electronic laryngoscope into the tracheal hose, and the tracheal hose coating the hollow hard tube with a camera circumferentially goes deep into patients' laryngeal cavity.
In the process of diagnosis, the camera of the electronic laryngoscope will be completely covered by the sputum inside patients' laryngeal cavity, influencing physicians' checking effect. Therefore, the sputum needs to be removed in time. However, it's always been a difficulty in hospital work to use the electronic laryngoscope while suctioning the sputum or nursing laryngeal cavity of patients, especially patients in coma. That's because method of sputum suction applying conventional auxiliary instruments often cannot achieve the object to clear the sputum and dirt in mouth thoroughly and, meanwhile, it is also inconvenient to operate due to the complicated and overloaded auxiliary instruments.
Chinese utility model patent CN203388832 (a hose laryngoscope) has disclosed an improved way of sputum suction. In order to suction out the sputum, in this utility model patent, the sputum suction catheter is buried in the wall of the tracheal hose and axially extends along the tracheal hose. The rear end of the sputum suction catheter is provided with a sputum aspirator interface and the front end thereof has a small opening (that is “sputum suction opening”) disposed on the inner wall of the front end part of the tracheal hose, and the sputum is suctioned out from the sputum suction opening through the sputum suction catheter.
Chinese utility model patent CN201168310 (a multifunctional light-emitting tracheal catheter) has also disclosed a solution of sputum suction, which has improvements similar to the utility model patent CN203388832. The sputum suction catheter is also buried in the wall of the tracheal hose, and the sputum suction opening is also a small opening which is disposed on the inner wall of the front end part of the tracheal hose.
In the above two utility model patents, the sputum suction catheter is buried in the wall of the tracheal hose, the defect of which is that the location of the sputum suction opening from the location of a camera cannot be determined. Under normal circumstances, the sputum suction opening would be in a position relatively far from the camera, for the specifications of the tracheal hose are relatively various and the sizes are different. According to the stipulations of the tracheal hose by Pharmaceutical industry standard YY0337.1-2002 of the People's Republic of China, there are 19 specifications on the tracheal hoses due to the difference of the inner diameter and the length matched with the inner diameter. Therefore, it is relative hard for the sputum suction opening disposed on the wall of the tracheal hose to match with or correspond to the location of the camera on the hollow hard tube, resulting in that the sputum or dirt around the camera cannot be removed or cleaned effectively.
Therefore, with respect to the prior art of the solution of sputum suction relative to the electronic laryngoscope, for the sputum suction openings are all far away from the camera or cannot be disposed stably around the camera and, meanwhile, the power of the sputum aspirator is relatively small (a relatively large sputum suction force would make patients feel uncomfortable, or injure their wall of laryngeal cavity), the sputum or dirt on the periphery of the camera cannot be removed effectively and completely. Even if the sputum suction opening happens to locate around the camera, the sputum around the camera cannot be removed effectively since the sputum suction can only be performed at a certain point on one side around the camera.